[automerge] Update fastboot version checking to 3103 to support P21 2p: 2573c7ce0a am: 56d83740c9

Original change: https://googleplex-android-review.googlesource.com/c/device/common/+/15720117

Change-Id: I637b82fd2c57ac45b5c28b74941cf1c80235e844